nojhan/paradiseo
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

fix eoProportionalSelect for negative fitnesses

Browse source
This commit is contained in:
Johann Dreo 2020-08-31 11:13:19 +02:00
commit 41e3d8a648
1 changed files with 35 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

50
eo/src/eoProportionalSelect.h
View file

@ -29,6 +29,9 @@
//-----------------------------------------------------------------------------
#include <iterator>
#include <utility>
#include "utils/eoRNG.h"
#include "utils/selectors.h"
#include "eoSelectOne.h"
@ -49,21 +52,33 @@ public:
/// Sanity check
eoProportionalSelect(const eoPop<EOT>& /*pop*/ = eoPop<EOT>())
{
if (minimizing_fitness<EOT>())
throw eoException("eoProportionalSelect: minimizing fitness");
if (minimizing_fitness<EOT>()) {
std::string msg = "eoProportionalSelect cannot be used with minimizing fitness";
eo::log << eo::errors << "ERROR: " << msg << std::endl;
throw eoException(msg);
}
}
void setup(const eoPop<EOT>& _pop)
{
if (_pop.size() == 0) return;
cumulative.resize(_pop.size());
cumulative[0] = _pop[0].fitness();
for (unsigned i = 1; i < _pop.size(); ++i)
{
cumulative[i] = _pop[i].fitness() + cumulative[i-1];
if (_pop.size() == 0) {
eo::log << eo::warnings << "Warning: eoProportionalSelect setup called on an empty population." << std::endl;
return;
}
assert(not _pop[0].invalid());
const typename EOT::Fitness min_fit
= std::min_element( std::begin(_pop), std::end(_pop) )
->fitness();
cumulative.clear();
cumulative.push_back(_pop[0].fitness() - min_fit);
for (unsigned i = 1; i < _pop.size(); ++i) {
assert(not _pop[i].invalid());
cumulative.push_back(cumulative.back() + _pop[i].fitness() - min_fit);
}
assert(cumulative.size() == _pop.size());
}
/** do the selection,
@ -72,9 +87,18 @@ public:
{
if (cumulative.size() == 0) setup(_pop);
double fortune = rng.uniform() * cumulative.back();
typename FitVec::iterator result = std::upper_bound(cumulative.begin(), cumulative.end(), fortune);
return _pop[result - cumulative.begin()];
double frac = rng.uniform();
double fortune = frac * cumulative.back();
typename FitVec::iterator result
= std::upper_bound(cumulative.begin(), cumulative.end(), fortune);
assert(fortune <= cumulative.back());
if(result - cumulative.begin() == _pop.size()) {
return _pop.back();
} else {
return _pop[result - cumulative.begin()];
}
}
private :